An Electro Hydro Dynamic, EHD, thruster (105) comprising a first set of electrodes (210), a second set of electrodes (220) and a supporting structure (103) for supporting the first set of electrodes (210) and the second set of electrodes (220). The EHD thruster (105) is configured to generate airflow of ionized air for cooling a heat sink (101). Further, the EHD thruster (105) is electrically isolated from the heat sink (101).

Systems and/or methods can provide for solid-state refrigeration below 1 degree Kelvin. By applying a simple sequence of ac electrical signals to a gated semiconductor device, electrons are cooled in a refrigeration sequence that, in turn, provides cooling directly to the heat load of interest. Electrons in a single subband of a semiconductor quantum well are expanded adiabatically into several subbands, resulting in a temperature drop. Repeated application of this cycle at MHz-GHz frequencies results in a significant cooling power. The anticipated cooling powers can compete with today's standard cryogenic system, the dilution refrigerator, which represents the market standard for achieving cryogenic temperatures.

A solid state cooler device is provided that includes a substrate, a first and second conductive pad disposed on the substrate, a first and second superconductor pad each having a side with a plurality of conductive pad contact interfaces spaced apart from one another and being in contact with a surface of respective first and second conductive pads, and a first and second insulating layer disposed between respective first and second superconductor pads, and respective ends of a normal metal layer. A bias voltage is applied between one of a first conductive pad or first superconductor pad and one of the second conductive pad or the second superconductor pad to remove hot electrons from the normal metal layer, and the contact area of the plurality of first and second conductive pad contact interfaces inhibits the transfer of heat back to the first and second superconductor pads.

A superconductor thermal filter is disclosed that includes a normal metal layer having a first side, an insulating layer overlying the first side of the normal metal layer, and a multilayer superconductor structure having a first side overlying a side of the insulating layer opposite the side that overlies the normal metal layer. The multilayer superconductor structure is comprised of a plurality of superconductor layers with each superconductor layer having a smaller superconducting energy band gap than the preceding superconductor as the superconductor layers extend away from the normal metal layer. The thermal filter further includes a normal metal layer quasiparticle trap having a first side and a second side with the first side being disposed on a second side of the multilayer superconductor. A bias voltage is applied between the normal metal layer and the normal metal layer quasiparticle trap to remove hot electrons from the normal metal layer.

Systems and/or methods can provide for solid-state refrigeration below 1 degree Kelvin. By applying a simple sequence of ac electrical signals to a gated semiconductor device, electrons are cooled in a refrigeration sequence that, in turn, provides cooling directly to the heat load of interest. Electrons in a single subband of a semiconductor quantum well are expanded adiabatically into several subbands, resulting in a temperature drop. Repeated application of this cycle at MHz-GHz frequencies results in a significant cooling power. The anticipated cooling powers can compete with today's standard cryogenic system, the dilution refrigerator, which represents the market standard for achieving cryogenic temperatures.

In an embodiment, a method includes, impinging a plurality of particles on a target such that electrons are emitted from the target and transporting the electrons from the target to a heat sink through a transporting medium. The target and the heat sink may be separated by a distance. The method further includes cooling the electrons using the heat sink and returning the electrons from the heat sink to the target.

A solid state cooler device is provided that includes a substrate, a first and second conductive pad disposed on the substrate, a first and second superconductor pad each having a side with a plurality of conductive pad contact interfaces spaced apart from one another and being in contact with a surface of respective first and second conductive pads, and a first and second insulating layer disposed between respective first and second superconductor pads, and respective ends of a normal metal layer. A bias voltage is applied between one of a first conductive pad or first superconductor pad and one of the second conductive pad or the second superconductor pad to remove hot electrons from the normal metal layer, and the contact area of the plurality of first and second conductive pad contact interfaces inhibits the transfer of heat back to the first and second superconductor pads.

A superconductor thermal filter is disclosed that includes a normal metal layer having a first side, an insulating layer overlying the first side of the normal metal layer, and a multilayer superconductor structure having a first side overlying a side of the insulting layer opposite the side that overlies the normal metal layer. The multilayer superconductor structure is comprised of a plurality of superconductor layers with each superconductor layer having a smaller superconducting energy band gap than the preceding superconductor as the superconductor layers extend away from the normal metal layer. The thermal filter further includes a normal metal layer quasiparticle trap having a first side and a second side with the first side being disposed on a second side of the multilayer superconductor. A bias voltage is applied between the normal metal layer and the normal metal layer quasiparticle trap to remove hot electrons from the normal metal layer.

Electron emission from an emissive substance, such as an emissive composite material, can be employed as a heat dissipation technique and mechanism for a part subject to operational heating. Emissive composite materials containing a refractory metal matrix and a ceramic electride material in the refractory metal matrix can be utilized for this purpose. Emissive composite materials can retain the thermal stability of the base refractory metal and emit electrons upon being heated to a sufficiently high temperature. Cooling systems and associated methods can utilize a collector configured to receive electrons emitted across open space by the ceramic electride material upon heating, and a conductive pathway can allow the electrons to be returned to the emissive composite material. Accordingly, the emissive composite material and the collector define a portion of an electrical circuit.

In an embodiment, a method includes, impinging a plurality of particles on a target such that electrons are emitted from the target and transporting the electrons from the target to a heat sink through a transporting medium. The target and the heat sink may be separated by a distance. The method further includes cooling the electrons using the heat sink and returning the electrons from the heat sink to the target.